We have found that recently accounts with leading zeros have lost their leading zeros in the processing flow.

It is potentially relateded to a change where the CSV files are being read by pandas in the download flow now without dtypes being specified and pandas is interpreting the account number as an integer and not a string.

https://github.com/project-koku/koku/blob/main/koku/masu/external/downloader/aws/aws_report_downloader.py#L116